Aloe ready for bioavailability applications

A study demonstrating the potential for aloe vera to enhance
vitamin C and B12 bioavailability could give manufacturers of the
ingredient another angle along which to promote it.

Researchers at the University of California at Davis Medical Center
set out to test the effect of two aloe vera preparations and
placebo in a human clinical trial, citing the motivation that
vitamin B12 is deficient in vegetarians and the aging population.
The UC Davis study demonstrated the potential for aloe to enhance
the bioavailability of vitamins C and B12, as well as ORAC.
The favorable results of this study, which is awaiting
peer-reviewed publication, back-up a previous study showing aloe
enhances the absorption of vitamin C and E, thereby potentially
opening up a new category for the use of aloe in dietary
supplements.
"Bioavailability is a very important topic in the dietary
supplement industry at this time,"​ Ken Jones, chief science
officer and president of the International Aloe Science Council
(IASC), told NutraIngredients-USA. "So this elevates aloe and
expands its uses."​
The IASC and the Aloe Institute funded both studies, in which the
company Aloecorp played no role, said Jones.
Aloe vera, from the tree lily family aloe
barbadensis​,​ has traditionally been used as an
all-purpose herbal plant. The aloe whole leaf extract or aloe
fillet gel can be used as functional ingredients in the form of a
juice or powder. In dietary supplements, ingredients derived from
the botanical have been used for immune support and relieving
oxidative stress.
The UC Davis randomized cross-over trial involved 15 participants
between 40 and 80 years of age who were given their vitamins with
either aloe whole leaf extract, aloe fillet gel, or just water. The
vitamins consisted of 1mg of vitamin B12 and 500mg of vitamin
C.
Blood was then obtained from the subjects following one, two, four,
six, eight and 24-hour post-ingestion of the aloe or water
combinations, with one week between treatments. Researchers
indicated that neither the aloe whole leaf extract nor the aloe
fillet gel affected lipid or glucose levels.
The aloe gel significantly increased plasma ORAC (Oxygen Radical
Absorbance Capacity) at both four and 24 hours while the aloe leaf
extract significantly increased it at four hours compared to
baseline and placebo (AUC, 24h, p<0.05).
The aloe gel was also said to have increased plasma vitamin C
levels four, six, eight and 24 hours following ingestion, while
aloe leaf extract raised the serum vitamin C levels at four and six
hours (AUC, eight and 24 hours, p<0.02).
According to the researchers, vitamin B12 was also increased in the
serum by both forms of the aloe ingredient at one and two
hours.
This could have implications for supplementation and the targeting
of chronic diseases, especially in the elderly, said Jones.
"One area of research - if you were going to go for that - is
to look at specific conditions which could benefit from increased
absorption,"​ said Jones.
The aloe specialist cited the example of gastrointestinal
conditions that make it even more difficult for people to absorb
vitamin B12. B12 is crucial to brain functioning, as well as for
the formation of blood.
The advantage of this most recent study, which is set to be
published in the FASEB Journal​ (published by the
Federation of American Societies for Experimental Biology),
according to Jones, is that it has set a dosing parameter for the
use of aloe vera and bioavailability.
"Now we have specific doses associated with a specific
action,"​ said Jones.
Aloe has established applications for cosmetics and dietary
supplements, as well as in the growing crossover category for these
two markets: cosmeceuticals. The application for bioavailability
would create a new category for uses in dietary supplements.
The previous aloe vera bioavailability study, published in 2005 in
the Phytomedicine​ journal, involved healthy subjects
ranging between the ages of 21 and 42. Aloe was found to improve
both the absorption of vitamins C and E.
It now remains for supplement makers to in turn test aloe
ingredients in their products. Like any other plant-derived
ingredients, aloe has its own shelf-life and stability challenges
which would have to be assessed, said Jones.
Source:
Vinson, J.A., H. Al Kharrat and L. Andreoli. "Effect of aloe vera
preparations on the human bioavailability of vitamins C and E."
Phytomedicine​. 12 (2005) 760-765.